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| <meta name="DC.Title" content="PARQUET_FALLBACK_SCHEMA_RESOLUTION Query Option (Impala 2.6 or higher only)" /> |
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| <title>PARQUET_FALLBACK_SCHEMA_RESOLUTION Query Option (Impala 2.6 or higher only)</title> |
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| <body id="parquet_fallback_schema_resolution"> |
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| <h1 class="title topictitle1" id="ariaid-title1">PARQUET_FALLBACK_SCHEMA_RESOLUTION Query Option (<span class="keyword">Impala 2.6</span> or higher only)</h1> |
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| <div class="body conbody"> |
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| <div class="p"> |
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| The <code class="ph codeph">PARQUET_FALLBACK_SCHEMA_RESOLUTION</code> query option allows Impala to look |
| up columns within Parquet files by column name, rather than column order, |
| when necessary. |
| The allowed values are: |
| <ul class="ul"> |
| <li class="li"> |
| POSITION (0) |
| </li> |
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| <li class="li"> |
| NAME (1) |
| </li> |
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| </ul> |
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| </div> |
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| <p class="p"> |
| <strong class="ph b">Usage notes:</strong> |
| </p> |
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| <p class="p"> |
| By default, Impala looks up columns within a Parquet file based on |
| the order of columns in the table. |
| The <code class="ph codeph">name</code> setting for this option enables behavior for |
| Impala queries similar to the Hive setting <code class="ph codeph">parquet.column.index access=false</code>. |
| It also allows Impala to query Parquet files created by Hive with the |
| <code class="ph codeph">parquet.column.index.access=false</code> setting in effect. |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Type:</strong> integer or string |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Added in:</strong> <span class="keyword">Impala 2.6.0</span> |
| </p> |
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| <p class="p"> |
| <strong class="ph b">Related information:</strong> |
| </p> |
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| <p class="p"> |
| <a class="xref" href="impala_parquet.html#parquet_schema_evolution">Schema Evolution for Parquet Tables</a> |
| </p> |
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| </div> |
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| <div class="related-links"> |
| <div class="familylinks"> |
| <div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_set.html">SET Statement</a></div> |
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